P.M.
This is surely copyrighted material, and if so, it is illegal to copy it. I hope people will admit that taking copyrighted material is harming whoever invested time and money and creativity in producing that material. They may have been living on beans for a year or three, hoping for an eventual return on their sacrifice and effort. Plus there are the additional costs of packaging, advertising, and distributing. It often takes years and many thousands of bucks to finally get a product worth selling, and then people feel free to "take" it.
I know of this personally. My husband and I produce modestly clever and original educational materials, and we live on a combined income equal to one schoolteacher. Users of our lessons will often nonchalantly report, (to us!) that they are sharing and trading our materials with colleagues in direct violation of our copyright restrictions, so we know we are losing sales.
Of course we will mention that this is a violation, which can be awkward right there, but we doubt that our needs will ever cross their minds even after explaining. It's just too convenient to cheat/steal/ignore those copyright notices. People are inclined to hear what they want, rationalize away what they don't want.
We've been hanging on by our fingernails for nearly 30 years because we know we are doing good work in the world. But it's financially challenging. Please respect other people's need to make a profit on their work.